France conducted the first at-sea firing of its latest submarine-launched ballistic missile on Tuesday, US Naval Institute News reports.
The French Navy’s nuclear powered ballistic missile submarine SNLE Le Vigilant (S618) launched an M51.3 SLBM – minus its nuclear warhead – off the coast of Finistère, France. The missile landed in the North Atlantic, several hundred kilometers from any coastline, reads a French Ministry of the Armed Forces and Veterans Affairs news release.
The launch was the first time the M51.3, which entered operational service on Oct. 24, 2025 had been launched from a submerged SSBN, and only the second time the missile had been fired – the first having been for a ground-based qualification in November of 2023.
“The firing of the M51.3 missile marks a significant milestone in maintaining the operational readiness of the oceanic component of France’s nuclear deterrent. In the presence of [French] President Emmanuel Macron, this operation demonstrates the capabilities of French industrial and military stakeholders and France’s commitment to preserving its strategic capabilities in the face of evolving threats,” reads the release.
The first at-sea firing was conducted as part of Operation Smertrios. The missile launch occurred after Le Vigilant’s periodic maintenance and repair and validated the submarine’s ability to deploy its weapon system.
The missile’s trajectory was monitored throughout its flight phase by the French Defense Procurement Agency (DGA/EM), primarily through the missile range instrumentation ship FS Monge(A601).
Macron watched the launch from frigate FS Auvergne (D654) and posted a video of the event on his X account.
“This technical success is a new demonstration of the credibility of our deterrence, whose sustainability is assured. To be free, one must be feared. And to be feared, one must be powerful,” reads Macron’s post.
The video also shows Macron making an address on the frigate.
“Today we are stronger. The message has been sent loud and clear for wherever it must be received,” Macron said in the video.
On Oct. 1 during a discussion forum, Russian President Vladimir Putin had reiterated that Russia has warned Western countries not to escalate the conflict in Ukraine by threatening the Russian enclave of Kaliningrad.
“We are not threatening anyone. We are simply stating that we do not have all that many means of defending ourselves. And, incidentally, neither that letter nor the Foreign Ministry’s statement mentions the use of nuclear weapons. They speak, as I have just put it, of employing all the forces and means available to our country. As for how that would actually happen, we will decide that ourselves,” Putin said, according to a Kremlin transcript.
France operates four Le Triomphant-class SSBNs, each carrying 16 SLBMs. Beginning in 2036, the submarines will be replaced by L’Invincible-class SSBNs.
The M51.3 is the third version of the M51 SLBM, which began deployment in 2010. The missile is capable of carrying its payload over an intercontinental distance of several thousand kilometers and can reach an altitude of more than 1242 miles, well beyond low-Earth orbit (LEO) and then re-enters the atmosphere at a speed of Mach 20, according to manufacturer ArianeGroup.
The company is currently developing the M51.4 SLBM, with work having commenced in September of 2025.
“The M51 missile program follows an incremental development approach to ensure it keeps pace with changes in the geostrategic context and France’s evolving needs. For ArianeGroup, the only European company capable of designing and producing a strategic missile, this means staying at the forefront of technology and maintaining the highest standards of performance,”reads an ArianeGroup news release.
